      
	One-dimensional scaling without apologies, Journal of Politics, forthcoming.
		
	Author: Tasos Kalandrakis


Materials in this replication package replicate the calculations reported in Table 4 of the main paper.


     
     Data

Survey data used in all calculations are included in the Matlab file GERN.mat and are sourced from the Comparative Study of Electoral Systems (2015, 2018).


     
     Duration of Replication Calculations

The calculations required to fully reproduce Table 4 take about 24 hours on a 24 core machine.



     Software Requirements 

Matlab is the only required software platform (the calculations have been verified in versions 2020a and later).



     Randomization Seed Setting

The computed tests rely on a bootstrap procedure.  Because the computations involved are distributed to multiple Matlab workers where the state of the seed may not evolve in a predictable manner and to ensure replicability of the results, the randomization seed is set before the execution of each test on line 97 of ModMAXTestTwoStep.m (with Matlab command rng(142536)).



     Warnings and Issues

No warnings or issues are encountered in the calculations reproducing Table 4.

     

     Detailed Replication Instructions

To fully replicate Table 4, Open Matlab and make the Dataverse folder your Matlab current folder.  Then execute the command:
 		
		ReplicateTable4

in the MATLAB command prompt.  This command produces and saves 12 files:
	M98F.mat
	M986.mat
	Ma02F.mat
	Ma026.mat
	M05F.mat
	M056.mat
	M09F.mat
	M096.mat
	M13F.mat
	M136.mat
	M17F.mat
	M176.mat
Table 4 is then built as a Matlab cell object that is displayed on screen in the Matlab variable window at the end of the replication. The Table entries that correspond to party orders are reported as Matlab cell objects that list the parties in order upon clicking on that Table entry. The Table was manually transferred into Latex by the author.



     Detailed File Contents

The following files are included as part of this Dataverse:
	1. README.txt (this file)
	2. ReplicateTable4.m (MATLAB script -- used to compute score estimator and tests to build Table 4)
	3. Codebook.pdf (Codebook describing variables in GERN.mat)
	4. UCombMAX.m (MATLAB function -- computes score estimator and tests for all six surveys)
	5. GERN.mat (MATLAB data file -- contains survey data used to run estimator and tests)
	6. ModMAXTestTwoStep.m (MATLAB function -- performs two-step procedure of Romano et al. (2014) using the MAX test statistic.  Originally distributed by Michael Wolf and modified and redistributed with permission as detailed in the copyright notice at the beginning of the file)
	7. RUMoment.m (MATLAB function -- evaluates moment function for (M_R) and (M_U)). 
	8. Folder 'SUPPLEMENTAL' (contains additional materials for the calculations in the Supplemental Appendix -- see file READMESUPP.txt of that folder for details)



     License for Matlab Code

The code that is redistributed and originates in the distribution by Michael Wolf is covered by the original license as explicitly included in the corresponding code files.  All other code is licensed under a Creative Commons/CC-BY-NC license.
	


     References

Romano, J. P., A. Shaikh and M. Wolf. 2014. "A practical two-step method for testing moment inequalities," Econometrica 82(5):1979-2002.

The Comparative Study of Electoral Systems. 2015, 2018. www.cses.org